Kirklin Clinic Specialty Pharmacy, University of Alabama at Birmingham Hospital, Birmingham, AL.
Am J Health Syst Pharm. 2020 Oct 30;77(22):1846-1851. doi: 10.1093/ajhp/zxaa268.
A case of a possible interaction between cannabidiol and warfarin is presented along with a brief overview of cytochrome enzymes involved in these drugs' metabolism.
A 46-year-old male taking warfarin for treatment of a deep venous thrombosis was initiated on a Food and Drug Administration (FDA)-approved cannabidiol product (Epidiolex, Greenwich Biosciences) for intractable epilepsy. The patient's International Normalized Ratio (INR) was monitored closely during cannabidiol initiation and dose titration. The patient required a nearly 20% warfarin dose reduction to maintain an INR within the goal range after starting therapy with cannabidiol. There is 1 other case report describing a clinically significant interaction between cannabidiol (specifically Epidiolex) and warfarin in a patient receiving warfarin who was enrolled in a study involving the initiation and titration of cannabidiol; that patient developed a supratherapeutic INR of 6.86 and required a 30% reduction in the weekly warfarin dose to reachieve the goal INR.
A previously published report suggesting an interaction between cannabidiol and warfarin is supported by this case report. INR should be monitored frequently in patients taking warfarin who begin to take FDA-approved cannabidiol. Additional studies should be performed to clarify the interaction potential of cannabidiol and warfarin.
本文报告了 1 例可能同时使用大麻二酚和华法林的病例，并简要概述了这两种药物代谢过程中涉及的细胞色素酶。
一位 46 岁男性因深静脉血栓接受华法林治疗，随后因难治性癫痫开始使用美国食品药品监督管理局（FDA）批准的大麻二酚产品（Epidiolex，Greenwich Biosciences）。在开始使用大麻二酚和调整剂量期间，密切监测该患者的国际标准化比值（INR）。开始使用大麻二酚治疗后，该患者需要将华法林剂量减少近 20%，才能将 INR 维持在目标范围内。有 1 例其他病例报告描述了 1 例接受华法林治疗的患者在使用大麻二酚（特别是 Epidiolex）时出现临床显著的相互作用，该患者参加了 1 项涉及大麻二酚起始和滴定的研究，INR 超过治疗范围（6.86），需要将每周华法林剂量减少 30%才能达到目标 INR。
本病例报告支持先前发表的报告提示大麻二酚与华法林之间存在相互作用。开始使用 FDA 批准的大麻二酚的同时服用华法林的患者，应频繁监测 INR。应开展更多研究以阐明大麻二酚与华法林相互作用的潜力。
